A method of forming a thin film on a base includes one of various methods such as a fine particle beam deposition process and an aerosol process.
According to the aerosol process, aerosol containing ceramic particles is sprayed from a nozzle toward a base to collide fine particles to the base. A ceramic coating film is then formed on the base using a colliding force. An example of a prior art about aerosol process is disclosed in Korean Patent Laid-open Publication No. 2002-0053563.
The fine particles allow ceramic particles having a nano size to be carried toward a surface of the base from a spray hole by a carrier gas. Then, while the ceramic particles pass through the spray hole, the ceramic particles may weaken particle fluidity with respect to the spray hole. This is because ceramic particles may be adhered to a spray hole, for example, a nozzle, and a supply line connecting the nozzle with a feeder by static electricity while carrying thereof. In this case, the spray hole may be clogged due to the ceramic particles adhered to the spray hole. As a result, the ceramic particles are non-uniformly supplied to the surface of the base, so that an adhesive force between a ceramic coating film formed by the ceramic particles and the base may be weakened and further plasma resistance of the ceramic coating film may be worsened.